No offense, but you are probably doing it wrong. Headphones are simply different. Do not take a preset that is good through HPs and audition that with other speakers. Create and tweak new patches only using normal speakers until you like them. If you cannot do that then probably get some better speakers / modeler. If you get a good sound with normal speakers, listen to that preset with HPs. It will probably sound not as good. Also play with reverb a bit and see if it helps.